Study Guide Midterm 1 Flashcards
The seven properties of life:
1.- order
2.- response to environment
3.- regulation
4.- reproduction
5.-growth
6.- energy processing
7.- evolutionary adaptation
The three domains of life:
1.- Bacteria
2.- Archaea
3.- Eukarya
Bacteria
Cells do not contain a nucleus
Archaea
Cells do not contain a nucleus; they have a different cell wall from bacteria.
Eukarya
Cells do contain a nucleus, and divided in kingdoms (fungi, animals and plants)
The 10 levels of organization:
- Biosphere
- Ecosystem
- Community
- Population
- Organism
- Organs and organ system
- Tissue
- Cell
- Organelle
- Molecule
Emergent Properties
arise out of each increased level of complexity (eg. Ability to evolve arises when individual organisms combine to form populations.
Form and function
are tightly linked, is the relationship between the shape, size, and structure of an organism, and how that structure allows for actions that aid the organism in survival.
Simple structure of organic compounds
- organic compounds, and they usually contains hydrogen atoms in addition to carbon.
- The carbon backbone allows for many different shapes.
- various functional groups can be attached to a backbone.
Macromolecules
Are Polymers, built from Monomers
Monomers
molecules that serve as building blocks
Polymers
Long molecule consisting of many similar building blocks (monomers)
Dehydration reaction
Occurs when Linked monomers together through the loss of water molecule.
Hydrolysis reaction
Polymers are disassembled into monomers by this reactions, which are essentially the reverse of dehydration reactions. Break polymers into monomers.
What are the four building blocks of life?
- Carbohydrates
- Proteins
- Nucleic Acids
- Lipids
Carbohydrate polymers can be also called?
Polysaccharides
What has in common carbohydrates & Monosaccharides?
- Monosaccharides are the monomeric form of carbohydrates
Which Carbohydrate polymers (Polyccharides) are used to store energy?
starch and glycogen
Which Carbohydrate polymers (Polyccharides) are used for structural fibres?
Cellulose and chitin
What are the three types of Lipids (or Fats)?
- Triacylglycerol (energy source and store in fat tissue)
- Phospholipids (two fatty acids)
- steroids (cholesterol)
Wha are Lipids?
large biological molecules that does not form polymers. They are hydrophobic (non polar)
Which are the roles of Lipids in energy storage?
Membrane formation and hormone signaling.
Lipids are Polymers?
No, they are not! They are hydrophobic.
What are proteins?
polymers composed of amino monomers.
Which are the four levels of Protein structure?
- Primary structure: a protein is its unique amino acids sequence.
- Secondary structure: coils and folds within the polypeptide chain.
- Tertiary structure: determinate by interactions among various side chains (R groups).
- Quaternary structure: a protein consists of multiple polypeptide chains.
What do proteins do?
- Enzymes (process that changes another molecule)
- scaffolds
- channels
- gates
- pumps
- motors, etc
Nucleic acids (DNA & RNA)
composed of nucleotide monomers.
Which are the five different nucleotide bases?
- adenine, A
- guanine, G
- cytosine, C
- thymine, T
- uracil, U.
What are the four nucleotide bases that are part of DNA?
- adenine, A
- guanine, G
- cytosine, C
- thymine, T
What’s the nucleotide base that is part of RNA?
- uracil (U)
What can be found within DNA molecule?
Information can be stored by linking together nucleotides in a particular sequence, (genes)
Prokaryotes
- oldest cell type
- small and simple
- lack of nucleus
- lack of organelles
- single-celled
Eukaryotes
- evolve from prokaryotes
- large and more complex
- contain nucleus
- contain organelles
- single-celled or multicellular
What is the molecular makeup of plasma membrane?
- 50% lipid
- 50% protein
- carbohydrate portions of glycolipids and glycoproteins constituting 5 to 10% of the membrane mass
What is the function of the plasma membrane?
- Provides protection
- transports nutrients in
- transports toxic substances out
Chromosomes
- they are made of protein
- could be found in animal and plant cell
- carries DNA
Ribosomes
- the cellular machinery responsible for making proteins.
- is made of RNA and protein
- is responsible of protein synthesis
Cytoplasm
- gelatinous liquid that fills the inside of a cell.
- is responsible for holding the components of the cell and protects them from damage.
Eukaryotic organelles
- Nucleus
- Ribosomes
- Smooth endoplasmic reticulum (SER)
- Rough endoplasmic reticulum (RER)
- Golgi apparatus
- Lysosomes
- Mitochondria
Nucleus
- Information Center for the cell
- contains DNA
Ribosomes
Responsible of making proteins.
Smooth endoplasmic reticulum (RER)
- no ribosomes on surface
- lipid synthesis and some synthesis of hormones.
- packaging of proteins and lipids for delivery to Golgi apparatus.
Rough endoplasmic reticulum (RER)
- has ribosomes on surface
- primary site of protein synthesis by ribosomes.
Golgi apparatus
Is responsible of refines, packages, and ships macromolecular products.
Lysosomes
Digests damaged organelles and cellular debris
Mitochondria
Produces energy (power plant of the cell)
Similarities that Prokaryotes & Eukaryotes have?
- have DNA
- have ribosomes
- have cytoplasm
- have plasma membrane
Eukaryotic Cytoskeleton
Provides internal scaffolding or organization of the cell
Roles and composition of Microtubules?
- Role in determine cell shape, cell movements, forms of cell locomotion, intracellular transport of organelles, an separation of chromosomes in cell division.
- composition of a single type of globular protein, called tubulin
Roles and composition of Microfilaments?
- Roles are assist with cell movement, or muscle cell contractions.
- the composition is two stands of actin monomers twisted into helical filaments that have intrinsic polarity.
Which are the types of cell-cell connections or junctions?
- tight junctions
- adhesion junctions/spot desmosomes
- gap junctions
Tight junctions
- seal plasma membranes tightly together
- digestive tract lining, bladder lining
Adhesion junctions/spot desmosomes
- buttons that keep the plasma membrane in place .
- permit some movement between cells
- allow tissues to stretch and bend
- skin
Gap junctions
- protein channels with movement of materials between cells.
- liver and heart.
Extracellular Matrix
- extracellular connective space between cells
- composed of glycoproteins (proteins bound with carbohydrate chains)
- the abundant glycoprotein is collagen (formed into long fibres)
- collagen fibres are then embedded in matrix of proteoglycans.
- cells are enforced to matrix by membrane proteins known as integrins.
Tissue
Integrate groups of similar cells that perform a common function.
Additional concepts to highlight
Protein manufacture, modification and shipping are core processes within a cell.
Additional concepts to highlight
Dynamic assembly and disassembly is a key property of microtubule/microfilament based cytoskeletal elements.
Additional concepts to highlight
Motor proteins interact with cytoskeletal elements to mediate movement of and within the
cell.
What’s the formation of biological membranes?
They are based of lipids
What’s fluid mosaic model of membranes?
Describes the structure of plasma membrane as a mosaic of components — including phospholipids, cholesterol, proteins, and carbohydrates— that gives the membrane a fluid character.
Passive transport
Transports a substance without having to expand energy, because it relies in diffusion, osmosis.
Active transport
Energy is required, Involves movement of molecules from a lower to height concentration against the use of external energy
Diffusion
Movement of molecules from a region of high to low concentration.
Osmosis
The diffusion of water molecules from a solution with high concentration of water to a solution with lower concentration of water molecules, though the cell’s partially permeable membrane.
Simple diffusion
The process in which a substance moves through a semipermeable membrane or in a solution without any help from transport proteins.
Facilitated diffusion
The diffusion of solutes through transport proteins in the plasma membrane.
How is active transport different and uses energy?
Uses energy to transport molecules across the plasma, It requires the use of energy (in the form of ATP)
Endocytosis and their function
Process in which cells take in substances from outside of the cell by engulfing them in a vesicle.
Exocytosis and their function
The process by which cells move materials from within the cell into the extracellular fluid, also removes toxins or waste products from the cell’s interior.
Cell division - Single celled organisms
In unicellular organisms, division of one cell reproduces the entire organism, (division=reproduction)
Cell division - Multicellular organisms
Multicellular organisms depend on cell division for (division=growth/replacement)
– Growth and development
– Repair/ renewal
- Canacer
Cell division
Before division, the chromosomes must be replicated.
Main distinctions between Binary fission and mitosis;
- Binary fission is a method of asexual reproduction which single-called organisms, usually prokaryotes, use to create a copy of themselves.
- Mitosis is a cell division that results in two identical daughter cells and is primarily used for growth of an organism.
Mitotic spindle
ensures that all chromosomes are correctly divided
Interphase
-(cell growth and copying of chromosomes in preparation for cell division)
-90% (or more) of typical animal cell’s life
- Time spent in each phase varies for different tissues,
different organisms.
- In a cell with a 24 hour cell cycle
Interphase can be divided into sub-phases
– G1 phase (“first gap”)
– S phase (“synthesis”)
– G2 phase (“second gap”)
Mitotic phase
• 1 to 1.5 hr
• basic steps are conserved throughout the eukaryotes;
• dominated by rearrangements of the cytoskeleton
Mitosis
is conventionally divided into five phases
– Prophase
– Prometaphase
– Metaphase
– Anaphase
– Telophase
• Cytokinesis overlaps latter stages of mitosis
Diploid
The presence of two complete sets of chromosomes in an organism’s cells, with each parent contributing a chromosomes to each pair.
23
Humans have 23 pairs of chromosomes
46
In all 23 from the mom and 23 from the father = 46 chromosomes
44 +2
44 autonomies and 2 sex chromosomes
Cancer
In cancer the cell cycle is dysregulated due to mutations .
Dysregulated mitosis
Is the common feature of all cancers.
Replication
Is the synthesis of an identical copy of the chromosomes. It occurs during the life of the cell prior to cell division.
Differences between homologous chromosomes & replicated chromosomes
- homologous groomsmen consist of one chromosomes from each parent. 23 from each parent.
- replicated chromosomes during s place each chromosome is replicated.
What’s the key to populations and evolution?
Generic variability created by sexual reproduction is the key.
